Antivirus engines are commonly provided on computing devices to protect against risks of malware exploiting the devices to illegitimate ends. Some antivirus engines use virus signatures provided in virus definition files stored on a device in order to scan and identify files that are potentially malicious (e.g., a virus, worm, trojan, or other form of malware). In order to remain protected against the latest, constantly evolving threats, user devices may update their virus definition files on a regular basis to incorporate new virus signatures that are designed to detect newer malware. Once an item of malware has been detected on a device, the antivirus engine may take action to mitigate its threat, such as by quarantining or deleting the malware from the device.